board: constify struct node_info array

Add 'const' (also 'static' in some places) to struct node_info
arrays to save memory footprint.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/board/isee/igep003x/board.c b/board/isee/igep003x/board.c
index cc55bcc..965a009 100644
--- a/board/isee/igep003x/board.c
+++ b/board/isee/igep003x/board.c
@@ -211,7 +211,7 @@
 int ft_board_setup(void *blob, bd_t *bd)
 {
 #ifdef CONFIG_FDT_FIXUP_PARTITIONS
-	static struct node_info nodes[] = {
+	static const struct node_info nodes[] = {
 		{ "ti,omap2-nand", MTD_DEV_TYPE_NAND, },
 	};